Method of electric welding.



' 2 SHEETS-SHEET 1.

o e 66 I I a 4- ml Emmi? v i 0.. H. KIGKLIGHTER. METHOD OF ELECTRICWELDING.

APPLIOATION FILED JAN. 26,1914.

Pa'bqnted Jan.5,191 5.

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CHARLES H. xroxticnirna, or ATLANTA, GEORGIA.

manic!) or ELECTRIC WELDING.

Specification of Letters Patent.

Application filed January 26, 1914. Serial N 0. 814,384.

To all whom it ma concern:

Be it known t at I, CHARLES HLKICK- LIGHTER, a citizen of the UnitedStates, re-

sidin at Atlanta, in the county of Fulton and tate of Georgia, haveinvented new and useful Improvements in the Method of Electric Welding,of which the following is the specification.

My invention relates to a method Of jOIII- ing two pieces of metal bythe use of 1ntermediate metal,which is welded to both of the two' piecesand is softened and forced into grooved recesses so as to allow theunwelded faces of the two pieces to come into immediate contact.-

The previous art in electric welding plates has had to do mainly withthin sheet metal. In the electric welding of commercial plates by heavycurrents at low voltages, recourse has been had to the simple welding ofthe edges of the plates, edge to cdge,-or in welding in spots usuallythrough the double thickness of a lapped joint. In the edge to edgewelding, beside other difiiculties, it is troublesome to obtain a jointas strong and reliable as the plate in other places. In the spot weldingmethod, a weld is made through the plates at one small area at a timeby. pressing on either side thereof the terminals of an electriccircuit. 111 this operation there are several difficulties. Much of theheat is dissipated in the body ofthe plates. The copper terminals, whichof necessity must have a very small area of contact against the plates,are rapidly burned and worn away. Again, the spot Welded joint, onacount of its lack of con tinuity, is very apt to leak unless corked orotherwise sealed. The methods of Rietzel for multiple spot welding andfor coupling with a link, having upturned edges, as illustrated inPatents No; 928701 and l,0-l0,sl.18, respectively, are limited to thinsheet metal work in the practical application.

The primary object of this invention is to afford simple and economicalmeans for fastening plates or similar pieces of metal together by thefusing of an intermediate metal to each of the plates or pieces ofmetal.

The intermediate metal should consist of long wires, rods or barsrunning along the joint between the plates,-and so situated relative togrooved recesses that, as they are fused to the plates, they will alsosoften and be forced into these recesses so as to permit the u'nweldedsurfaces of the plates to come into immediate contact with each other.

Another object is to afford ample contact between the metal plates andthe copper welding terminals, and to eliminate the tendency of these toburn, fuse or wear away on account of heating. And at the same time, themethod affords means for confining the Patented Jan. .5, 1915.

greater portion of heat to a very limited area and volume at the placewhere it can be utilized. The elimination of heat from V the plates inlarge measure prevents trouble due to thedistortion of the work duringthe operation and to the setting up of dangerous stresses afterward.These of course'result from the usual heating and subsequent cool- 1ng.i

Another object is to definitely and positively contract the path of thecurrent to a limited area at the surfaces to be welded. It .will beapparent that the use of small pencil shape-d copper terminals does notaccomplish this as successfully. This is because the cross sectionalarea of the currents path at the surfaces of weld alw ays becomesgreater than the contact area of the ter- .minal inthe usual case (ifspot welding.

plates that a sufficient intensity of temperature cannot be obtained.method succeeds almost independently of the thicknesses of the plates.Cognizance is herein taken of the method shown by Rietzel of Figure 5,Patent 928,701. But in this case the intermediate metal disks, aftertheiweld is made, hold the plates.apart and is not suited to boiler andtank construction.

Another object is to afford means .for the construction of a butt typeof joint much stronger and more reliable than they simple edge to edgewelded joint. This, as will be seen, consists in welding over the edgeto edge weld one or more straps or welts to ciency of the otherwise weakjoint.

The present Still another object is to obtain a type of joint whichcombines the desirable qualities of continuity of weld, tightnessagainstleak- 10 the present invention.

age, great strength, economy of heatingcurrent, simplicity of oration,economy of time and expense, an elimination of plate distortion troublesand burning away of welding terminals by concentrating-the heat out 1n anumber of ways, which it is not at thei'point of fusion.

Fig. 1 is a sketch illustrating an end view, partially sectioned andpartially diagrammatic.- It illustrates one application of illustratinga partial side viewof the appa- I ratus of; Fig. 1. Fig. 3 shows theplates, welts and wires of one type of joint assem- -'bled just beforethe welts are welded on. 5 Fig. 1 shows the joint of Fig. 3 after thewelts are welded on. Fig. 5 illustrates the plates and wires in positionjust before welding up a simple lap joint by use of tu o wires. Fig. 6illustrates a slight modifica- 2 tion for a joint similar to that inFig. 5.

Fig. 7 illustrates the joint of Fig. 6 after the welding. operation.Fig. 8 illustrates the plates and a wire in position before the welding,in which one wire is used. Fig. 9. illus- '25 trates the. assembly ofthe welts, plates and .wires ready for the reinforcement of asimplebuttweld with one'welt. Fig. 10 illiistrates the plates inposition just before welding, in which astamped bar or rod is employedinstead of the wire. Fig. 11 illustrates the joint of Fig. 10 afterwelding. Fig. 12 illustrates a wire form constructed foruse with a weltin Figs. 1, 2, 3 and 4:. Fig. 13 illustrates a special grooved welt foruse with the wire form of-Fig. 12. Fig. 14

illustrates another type of wire form con-' structed for use as in Fig.9. Fig. 15 illustrates: a grooved Welt for use with the wire form ofFig. 14. Fig. 16 illustrates a form stamped from sheet ironand for usein cases similar to Figs. 10 and 11. Fig. 17 shows the plates, welts andwires of Figs. 1 and 2 assembled before the welts are welded on. Fig. 18shows the joint of Figs. 1, 2 andv 17 -after'the welts are welded on.Fig. 19 is a top; view 'of Fig. 18,. Fig. 20 is a wire form-with spheresfor use in Fig. 17. Fig. 21 is the top view of a simple lapped-joint inwhich the wire and sphere construction is used. Fig. 22 is'a wire andsphere for use in Fig. 21. Fig. 23 is a side view taken at A'-A of F ig.21 before welding. Fig. 24 is a side view taken at BB of Fig. 21 beforewelding. Fig. 25 is a side view taken at A-A of Fig. 21 after welding.Fig. 26 is a side view taken at 13-15 of Fig. 21 after welding.

In order that the method may be more clearly understood, reference willbe made first to Figs. 1, 2. 3 and 4. Plates 1 and 2 "'areforced towardeach other, edge to edge, by forces 77p. Switch s is closed so that,heavy electric current supplied by transformer t, is transmitted betweenplates 1 and 2 across the line of edges in contact at 3.

Fig. 2 is a sketch plates -1--2, the welts 4 I wires 6-6, before beingsubjected to pres- 110 sure and the electric welding current.

"effects a weld between the abutted edges at 3 of the plates 1 and 2.This part of the operation is old in the art and may be carried deemednecessary to describe here.- This part of the operation is incomplete asa satisfactory and strong welding operation. This invention has to dowith the completion or satisfactory finishing up of this weldingoperation. Strips of metal or welts 4 r and 5 are introduced intoposition on either side of the plates 1' and 2 so as to bridge the jointat 3. These welts are held out of actual contact with the plates bywires or bars '66, which rest preferably in grooves "(-7. These wires orbars ma be cylindrical or otherwise shaped. he grooves should be ofaboutthe samevolume as the wires or bars and of such shape that theywill lie loosely therein 'andproject without and above these grooves.The copper conductor bars 8-9 are introduced into contact with the outersurface of the welts 4.--5 so 90, that one or more wires 6-6 liedirectly between them. Conductor-bars '89 may be supplied with a heavywelding current by transformer T when switch S is closed. At the sametime pressure rollers 1011 exert force PP through the conductor bars 89and the welts 1 5 to the wires 66. As

these pressure rollers 1011 traverse the joint lengthwise they areimmediately foland a second set of pressure rollers I l-15. The functionof the blades is to break contact between the copper conductors 8,-9 andthe welts 15. The function of the pressure rollers 14l-15 is to maintainpressure on the welts.45 after the passage of the electric current sothat a weld may be efi'ectedv Fig. 3 illustrates the assemblage of the 5with simply the Fig. 4 illustrates the'welded joint after" the operationon both sides of 'the butt weld- 3. The metal composing the wires 6-43has been welded to both welts and plates and simultaneously forced andpacked into thegrooves 77 until the surfaces of plates and we tscome-into immediate contact.

Fig. 5 illustrates a lapped joint between two plates 1-2, in which twowires 6-6 are employed In each plate is milled one slot 7-7. Thepressure blocks 8-9 also serve as terminals for applying the heating-current.

two plates 12. similar to that of Fig. 5, except'that half the volume ofthe wire is milled from each plate instead of the whole Fig. 6illustrates a lapped joint between 125.

welding operation. This is theoretically .gpod, but may be diflicultinsome construcbetween two plates in which one wire is employed. As thisjoint may be rather weak, occasional rivets or spot welds may be usedthrough the. lap to strengthen it.

Fig. 9 illustrates a butt joint in which the plates are brought togetheredge to edge, and a welt or strip is fastened to g each of the plates bythe method herein described.

Instead of the use of independent wires, a frame work of wire may beused and. slots cut into a welt 'to correspond with this frame. Fig. 12illustrates four parallel wires connected by cross wires. I Fig. 13illustrates the: welt to be used in conjunction with this-when making ajoint similar to that in Figs. 3 and 4.

. Fig. 14 illustrates two parallel wires conriccted by two diagonalcross wires. Fig. 15 illustrates the welt to be used in conjunction withthis, in making a joint similar to that in Fig. 9. 1

It is evident that stamped frames of thin sheet metal may be used. Fig.16 illustrates four bars 6-6-6-6 which have been stamped from thin sheetmetal and given a V or U shape. These may be inserted in grooves as 7 ofFig. 10. The spring between the'forks of bars 6 will serve to hold themin the slots and thus facilitate handling. After the weld has beenmadethe joint will appear as in Fig; 11.

i Fig. 17 illustrates the joint of Figs. land 2,.and one similar toFigs. 3 and 4 except that small lugs of metal 16-16, preferably in theshape of spheres, have been strung on the wires 6-6. Cup-shapeddepressions 17-17 have been cut from the surfaces in contact, preferablyfrom the welt. These depressions may be cut partly from both surfaces..Their function relative to the spheres 16-16 is the same as that of theg1'ooves 7-7 relative to the wires 6-6.

. Fig. 19 illustrates the welt 4 of Fig. 17 in place, spanning the buttweld 3 between the plates 1 and 2. Cup-shaped depressions 17-17 and thewelts.

Fig. 20 illustrates the wire frame 6-6 16-16 movable thereon. Theseframes are introduced between the plates 1 andQ and the welts 4-5, carebeing taken to slip the spheres along until each falls in acorresponding depression. If the spacing of depressions 17-17 iscarefully made to a definite distance, spheres 16-16 may be fixedrelative to wires 6-6.

After the plates. welts. wires and spheres as assembled in Fig. 17 aresubjected to grooves 7-7 have been cut from 66 presume and heatingelectric current, the

completed welded joint is made as illustrated in Fig. 18. The spheresliave'been welded to both plates and welts and forced forced while inthe plastic condition-into the voids made by the grooves.

Fig. 21 illustrates a, simple lapped joint made by welding to bothplates an intermediate metal forced into voids between the plates.

Fig. 22 shows the 'Wire- 6 with the spheres 16-16, which are used in thejoint of Fig. 21. Figs. 23 and 24 illustrate the relative positions oflates at A-A and B-B, respectively; of Fig. 21 before the weld. Figs. 25and 26 represent the same positions after the weld.

The operation is as follows: Referring to Figs. 1, 2, 17 and 18, plates1 and 2 are forced into contact edge to edge by forces 79-7), switch 8is closed and electric current from transformer t passed between plates1 and2 across the resistance of contact 3. The metal of the plate edgesis welded at 3, by the simultaneous heating and mechanical pressure. Theapplication of the forces 12- and electric terminals from transformer tare moved along the joint from end to end as the operation proceeds soas to-obtain a continuous butt weld. The welts 4-5, wires 6-6, spheres16-16 and electric conductors 8-9 are now brought into proper place. Theswitch S to transformer T is now closed. Heavy heating and weldingcurrent now flows between conductors 8-9 through welts 4-5, wires 6 orspheres 16, and the plate 2 or 1. The passage of this current takesplace directlybetween the rollers 10 and 11. The

1 wires and spheres are sinmltaneously welded to both welts and to theplate and are forced In their heated and plastic condition into thecorresponding grooves and depressions so as to fill the same and allowthe welts to come into immediate contact with the plates. The rollers10-11 traverse the seam from end to end and make a continuous weld asthey go. They are followed by blades 12-13 which separate the conductors8-9 from the welts 4-5, and thus interrupt the current through thecompleted weld. The blades are not absolutely necessary, as the contactresistance between the copper conductors and the welts varies inverselyas the applied mechanical pressure. Thus the flow of current will bevery small except under the pressure rollers 10-11. These rollers arefollowed by another pair of pressure rollers 14-15, bearing directly onthe welts 4-5 and holding the heated metals gether until a weld iseffected;

It is to be understood that the inventor does not limit himself waherein he .1.

. pressure and the electric current. It is apparent that pressureblocks, which also serve as electric terminals, may be moved toward eachother by rectilinear motion against the welts, and may be moved step bystep along the same. Other methods may also be employed. v

It will be apparent that the percentage of heat developed in thewelts-and the plate and thus wasted is small, on account of the broadarea of path which the electric current has in these. The most of theheat is 'developed in the wires 66 and the-spheres 16-16, and especiallyat the contact sur-' faces of these with the plates. This is because ofthe greatly restricted and contracted area of path here afforded theclec tric current. This is the valuable point of the invention. Nearlyevery particle of this heat is utilized,that at the wire and spherecontact surfaces forwelding purposes, that in the body of the wires andspheres for making them plastic so that they can be readily forced intothe grooves. and-recesses until the plate surfaces come into immediatecontact. It will also be apparent that when the pressure is firstapplied, theoretically there is but line contact between thewires andthe surfaces on either side, and only point contact-between the spheresand the surfaces. Due to the intense heat developed at this veryrestricted path for the current, the Welding may actually begin beforethe body of the wire or sphere begins to soften much, and thus thewelding of the wire or sphere to each surface will be from the centeroutward. The intensest heat will be developed at the center line of thepath of weld. In practice it may be found that the volume of theintermediate metal should be slightly more or less than the'volume ofthe voids. However, they should be about the same. It is also apparentthat the herein described method of fastening pieces of metal togetheris not limited to plates and sheets, but maybe applied to beams, angleirons, structural forms, and the like.

Vhat I claim is:

1. The method of fastening two pieces of metal together, face to face,consisting of cutting grooves in the faces of said pieces, of bringingsaid pieces into the desired juxtaposition, of introducing metallicWires or bars into said grooves with a portion of their lateral surfacesprojecting without the grooves so as to hold the said pieces ofmetalapart, and of welding the wires or bars to both of said pieces of metalby the application of pressure and heating electric current.

2. The method of fastening'two pieces of metal together, face to face,consisting of y cutting grooves in the faces of said pieces,

of bringing said pieces into the desired jux taposition, of introducingmetallic" wires or bars into said grooves with a portion of masses theirlateral surfaces projecting without the grooves so as to hold the saidpieces of metal apart, and of simultaneously forcing the Wires or barsinto the voids of the grooves and welding them to both of said pieces ofmetal by the application of pressure and heating electric current.

3. The method of fastening twopieces of metal together, face to face,consisting of cutting voids from the surfaces of said pieces, ofbringing said pieces into the desired juxtaposition, of introducingmetallic bodies into said voids with a portion thereof resting on thebottom of the voids and a portion thereof projecting without the voids,so as to hold the said ieces of metal apart, and of' welding the mtallic bodies to bothof said pieces. of metal by the applica tion ofpressure and heating? electric current.

4. The method of fastening two pieces of metal together, face to face,consistingiof cutting voids from the surfaces of said pieces, ofbringing said pieces into the desired juxtaposition, of introducingmetallic bodies into said voids with a portion thereof resting on thebottom of the voids and a portion thereof projecting without the voids,so

as to hold the said pieces of metal apart, and of simultaneously forcingthe bodies into conformity with the voids and welding them to both ofsaid pieces of metal by the application of pressure and heating electriccurrent.

5. The method 'of fastening two pieces of metal together, face to face,consisting of cutting grooves in the faces of said pieces, of

bringing said pieces intothe desired juxtaposition, of introducingmetallic wires or bars into said grooves with a portion of their lateralsurfaces projecting without; the grooves so as to hold the said piecesof metal apart, of forcing portions of the electrically heated wires orbars into the voids of the grooves and of snnultaneously welding saidportions to both of said pieces of metal by the application ofpressureand heating electric current.

6. The method of fastening two pieces of metal together, face to face,consisting of cutting grooves in the faces of said pieces, of bringingsaid pieces into thedesired juxtaposition, of introducing metallic wiresor bars into said grooves with a portion of their lateral surfacesprojecting 'without the of bridging their line of division by a striprunning along and in the direction of said line of division, ofintroducing metallic bodies in the voids, and by the application ofpressure and electric heating current of Welding the said metallicbodies to said strip and plates and at the same time forcing them intothe voids.

8. The method of fastening metal plates, edge to edge, consisting ofcutting voids in the surfaces or a surface ofdesired contact, ofbridging their line of division by strips running along and in thedirection of said line of division and on both. sides of the plates, ofintroducing metallic bodies in the voids and by the application ofpressure and electric heating current of welding the said metallicbodies to said strips and plates, and at the same time forcing them downinto the voids.

9. The method of fastening two metal plates by one or more auxiliaryplates, consisting in cutting grooves in said auxiliary v plate orplates, in bringing the parts into the desired juxtaposition with thegrooves parallel to the edges of the main plates in introducing wires orbars in the grooves, and in Welding the said Wires or bars to the mainand to the auxiliary plates by the application of pressure and heatingelectric current.

1.0. The method of fastening two pieces of metal together, face to face,consisting of cutting voids from the'surface of one of said pieces, ofbringing said pieces into the desired juxtaposition, of introducingmetallic bodies into said voids with a portion thereof resting on thebottom of the voids and a portion thereof projecting Without the voids,so

as to hold the said pieces of metal apart, and

lateral surfaces projectin of welding the metallic bodies to both ofsaid pieces of metal by the application of pressure and heating electriccurrent.

11. The method of fastening two pieces of metal together, face to face,consisting of cutting a groove in the face of one of said pieces, ofbringing said pieces into the desired juxtaposition, of introducing ametal- 12. The method of fastening two pieces of met al together, faceto face, consisting of cutting a groove or grooves in the face or facesof one or more of said pieces of metal, of bringing said pieces into thedesired juxtaposition, of introducing metallic wires or bars into saidgrooves withv a portion of their without the grooves so as to hold thesai pieces of metal apart, of forcing by a gradual andcontinuo'us'pressure from end to end of said seam, portions of theelectrically heated wires or bars into the voids of the grooves, and ofwelding said portions to both of said pieces of metal by the applicationof pressure and heating electric current.

In testimony whereof, I have hereunto signed my name in the presence oftwo subscribing witnesses at Atlanta, in the county of Fulton and Stateof Georgia, this 24th day of January, 1914.

CHARLES H. KICKLIGHTER.

Witnesses:

C. H. MoAoAivrs, W. A. MEDLOCK.

